PCA8565TS/1 [NXP]

PCA8565TS/1 is a real-time clock and calendar IC manufactured by NXP Semiconductors. It is a low-power CMOS RTC device designed to provide accurate timekeeping and calendar functions for embedded electronic systems. The device supports seconds, minutes, hours, day, date, month, and year information, and it communicates with a host microcontroller through a standard I²C-bus interface with data transfer rates up to 400 kbit/s.

The PCA8565TS/1 integrates an on-chip 32.768 kHz oscillator circuit for use with an external crystal, helping the system maintain stable clock operation. It includes programmable clock output, alarm function, timer function, interrupt output, and voltage-low detection, making it suitable for systems that need scheduled wake-up, event timing, timestamping, and backup timekeeping.

This RTC device is commonly supplied in an 8-pin TSSOP surface-mount package. It is designed for low-power operation and is suitable for battery-backed or standby-powered applications. The commonly listed supply voltage range is 1.8 V to 5.5 V, allowing compatibility with both low-voltage and 5 V embedded systems. The device is also listed with a wide operating temperature range of -40°C to +125°C, making it suitable for automotive, industrial, and general embedded applications.

In short, PCA8565TS/1 is an NXP low-power I²C real-time clock/calendar IC with integrated oscillator support, alarm, timer, programmable clock output, interrupt output, voltage-low detection, and compact 8-TSSOP packaging. It is mainly used in embedded systems, automotive electronics, industrial control equipment, smart meters, battery-powered devices, data loggers, and other products that require reliable timekeeping and calendar functions.

Key Features

• AEC-Q100 compliant for automotive applications
• Provides year, month, day, weekday, hours, minutes, and seconds based on 32.768 kHz quartz crystal
• Clock operating voltage: 1.8 V to 5.5 V
• Extended operating temperature range: -40 °C to +125 °C
• Low backup current: typical 0.65 μA at V_DD = 3.0 V and T_amb = 25 °C
• 400 kHz two-line I²C-bus interface (at V_DD = 1.8 V to 5.5 V)
• Programmable clock output for peripheral devices (32.768 kHz, 1.024 kHz, 32 Hz, and 1 Hz)
• Alarm and timer functions
• Two integrated oscillator capacitors
• Internal Power-On Reset (POR)
• I²C-bus target address: read A3h; write A2h
• Open-drain interrupt pin

Key Features

1. Integrated real-time clock/calendar
PCA8565TS/1 provides clock and calendar information including year, month, day, weekday, hours, minutes, and seconds, making it suitable for systems that need reliable timekeeping.

2. 400kHz I²C-bus interface
All address and data transfers are handled through a two-line bidirectional I²C-bus, with a maximum bus speed of 400kbit/s, allowing easy connection to MCUs, processors, and embedded controllers.

3. Low-power CMOS design
The device is optimized for low power consumption, which is important for battery-backed, standby, and energy-sensitive systems.

4. On-chip 32.768kHz oscillator circuit
The PCA8565 includes an on-chip 32.768kHz oscillator circuit with an integrated capacitor, reducing external component requirements and supporting standard RTC crystal operation.

5. Programmable clock output
The chip provides a programmable clock output / square-wave output, which can be used as a reference clock, timing signal, or low-frequency system clock source.

6. Alarm and timer functions
Integrated alarm and timer functions can generate interrupts for scheduled events, periodic wake-up, timed control, and low-power embedded system operation.

7. Voltage-low detector
The built-in voltage-low detector helps identify invalid or unstable clock operation caused by low supply voltage, improving reliability in backup or battery-powered systems.

8. Wide supply-voltage range
Distributor data commonly lists the device with a 1.8V to 5.5V supply range, making it compatible with many low-voltage and 5V embedded platforms.

9. Automotive-capable temperature range
The part is listed with a -40°C to +125°C operating temperature range and appears in automotive RTC references, making it suitable for harsh embedded and automotive environments.

Automotive

1. Automotive Time Keeping
2. Metering

3. Application Area	Typical Use
   Embedded systems	System timekeeping, timestamping, scheduled wake-up functions
   Automotive electronics	Timekeeping in battery management, engine control, and motor control systems
   Industrial control	Event logging, maintenance timing, control-board time reference
   Battery-powered equipment	Low-power clock/calendar function during standby
   Data loggers	Timestamping sensor readings and stored records
   Smart meters	Time-based metering, tariff timing, event records
   Consumer electronics	Clock/calendar function in appliances, displays, and smart devices
   Alarm and monitoring systems	Alarm scheduling, timed events, and interrupt-driven wake-up